TRANSACTIONS OF SECTION C. 519 



Recent Classifications op the Upper Eocenes. 



Professor Judd, in a paper communicated to the Geological Society in May, 1880, 

 on the Oligocene strata of the Hampshire basin, having reference to the beds at 

 Headon Hill and Colwell Bay, in the Isle of Wight, endeavoured to show that tlis 

 Colwell Bay marine beds are not, as has been hitherto supposed, the equivalents of 

 those of Headon Hill and Hordwell Clifi", but that they occupy a distinct and much 

 higher horizon in the Eocene series. Assuming this to be the case, a new classifica- 

 tion and nomenclature for the Upper Eocene series of Britain was proposed by the 

 author.' 



Professor Judd traced tlie liistory of previous opinion upon the succession of the 

 Tertiary strata down to the time of Professor Edward Forbes and the Geological 

 Survey, with the subsequent labours of Mr. Bristow. Edward Forbes confirmed tlie 

 previous determinations of Professor Prestwich in his elaborate researches in the Isle 

 of Wight Tertiaries. Forbes's life, however, was not spared to enable him to com- 

 plete his researches in this division of the British strata; his attention was chiefly 

 confined to the four uppermost Eocene members, or the Hempstead, Bembridge, 

 Osborne and St. Helen's, and tlie Headon beds. These divisions were accepted and 

 worlied upon as a basis by the Geological Survey. With regard to these strata, 

 Forbes maintained, as almost all previous observers had done, that the beds at Colwell 

 and Totland Bays are on the same horizon as those at the base of Headon Hill 

 and at Hordwell Clifl'. 



Professor Judd's view has been questioned and refuted by Messrs. Tawnej^ and 

 Keeping, in an elaborate paper also read before the Geological Society in May, 1881,^ 

 and in a subsequent communication to the Cambridge Philosophical Society in the 

 same year, ' On the Beds at Headon Hill and Colwell Bay in the Isle of Wight.' 



The importance of a correct reading and classification of these Middle Eocene 

 strata in the Isle of Wight, and their correlation with beds of the same age in 

 France, Belgium, 'and Germany, cannot be overlooked or over-estimated, and often as 

 it has been attempted, the papers by the two above-named authors have still greatly 

 added to our knowledge of the stratigraphy of the Eocene series of the Isle of Wight , 

 It is impossible to dispute the validity of their researches and value of their sec- 

 tions. The publication of Mr. Judd's paper disputing the correctness of Forbes's 

 work and tliat of the Geological Survey, and the proposal of a fresh classification, 

 drew immediate attention to the labours of the older authors, but especially that by 

 the Geoliigical Survey^wliich was answerable for the latest, indeed the only known 

 extended and complete analysis of the Upper Eocene strata of the Isle of Wight. 



We owe a debt of gratitude to the late Mr. F. Edwards and Mr. S. V. Wood, 

 for their valuable additions to our knowledge of the palreontology of the fauna of 

 the fluvio-mariue beds of the Hampshire basin. Since the publication of Professor 

 Forbes's memoir upon the Isle of Wight, the molluscan fauna alone is at least three 

 times as great as noticed by him, and since that time the remarkable fauna of 

 Brockenhurst in the New Forest, discovered by Mr. Edwards, has been carefully 

 studied by Von Konen for the mollusca, and Professor Duncan for tlie corals. These 

 naturalists have shown the agreement of this fauna with that of the Lower 

 Oligocene in North Germany. This Brockenhurst fauna is also identical with cer- 

 tain strata at the base of the IMiddle Headon beds at Whitecliff Bay, in the Isle of 

 Wight. 



Professor Judd in his paper describes the stratigraphical position of the Colwell 

 Bay and Headon Hill beds, and their relation to each other, pointing out what 

 he believed to have been an error on Forbes's part, relative to the correlation of the 

 ' "S'enus bed ' at the two places, in what is really a continuous section : Edward 

 Forbes and the Geological Survey having carefully and correctly determined that 

 only one set of marine strata occurred between the two brackish or estuarine and 

 freshwater series. This fact has been again most carefully worked out by Messrs. 

 Tawney and Keeping, leaving no doubt as to the inter|n-etation and accuracy of the 

 work of Forbes and the Sun'ey, and establishing upon a firmer basis the continuity 



' Quarterly Journal of the Geological Society, vol. xsxvi. p. 137. 

 * IMd. vol. xxxvli. p. 85. 



